Pharynx, Larynx, Thyroid and Sinuses Flashcards
What provides motor and sensory function to the larynx?
Branches of the vagus (cranial nerve X)
What innervates all intrinsic muscles of the larynx EXCEPT the cricothyroid?
Recurrent laryngeal nerve
Where is the larynx located?
Anteriorly in the neck, between C3-C6
What can be found anteriorly and laterally to the larynx?
Anteriorly - infrahyoid muscles
Laterally - lobes of the thyroid gland
What is the larynx a component of?
The voice box
Which arteries supply the larynx?
Superior and inferior laryngeal arteries.
S. (branch of S. Thyroid artery derived from external carotid)
I. (Branch of I. Thyroid artery derived from thyrocervical trunk)
In the larynx venous drainage is carried out by…
Superior and inferior laryngeal veins
S. Drains to internal jugular vein via superior thyroid vein
I. Drains to L. Brachiocephalic vein via inferior thyroid vein
Name the 3 parts to the pharynx
Nasopharynx
Oropharynx
Laryngopharynx
Which cranial nerve provides sensory function to the nasopharynx?
Branch of cranial nerve V - maxillary nerve (V2)
Which cranial nerve provides sensory function to the oropharynx?
Cranial nerve IX - glossopharyngeal
Which cranial nerve provides sensory function to the laryngopharynx?
Cranial nerve X - vagus
Which artery/arteries supply the pharynx?
Branches of the external carotid artery - ascending pharyngeal, lingual, facial and maxillary arteries
Which vein/veins are involved in venous drainage of the pharynx?
Pharyngeal venous plexus which drains into the internal jugular
What is the origin and insertion of the superior constrictor muscle of the pharynx?
Origin - medial pterygoid plate and pterygomandibular raphe
Insertion - median raphe of pharynx and pharyngeal tubercle
What is the origin and insertion of the middle constrictor of the pharynx?
Origin - Greater and lesser horns of hyoid bone and stylohyoid ligament
Insertion - median raphe of pharynx
What is the origin and insertion of the inferior constrictor of the pharynx?
Origin - Thyroid cartilage and cricoid cartilage
Insertion - median raphe of pharynx
Name the 3 unpaired cartilages of the larynx
Thyroid, cricoid and epiglottis
Name the 3 paired cartilages of the larynx
Arytenoid, corniculate, cuneiform
Why might a patient develop hypocalcaemia after thyroid surgery?
If parathyroid glands are damaged, devascularised or removed during surgery. Effects may be transient or permanent
Where is the thyroid gland located?
C5-T1
What supplies blood to the superior part of the thyroid?
Superior thyroid artery which is a branch off the external branch of the common carotid
What supplies blood to the inferior part of the thyroid?
Inferior thyroid artery which arises from the thyrocervical trunk which is a branch of the subclavian
What is the function of the sternothyroid and thyrohyoid muscles (extrinsic laryngeal muscles)?
Sternothyroid - depress the larynx
Thyrohyoid - elevates the larynx
What nerve supplies the cricothyroid muscle?
External branch of superior laryngeal nerve
What is the motor and sensory function of the superior laryngeal nerve?
External branch is motor to cricothyroid muscle
Internal branch is sensory to laryngeal mucosa
What is the function of the longitudinal muscles of the pharynx?
To shorten and widen the pharynx. Also elevates larynx to prevent food entering airway
Where would you create an emergency airway?
Locate depression between thyroid and cricoid cartilage. Indication should be made in cricothyroid membrane
What is the function of the intrinsic muscles of the larynx?
Control shape of rima glottidis and length and tension of vocal cords
What is the function of the sinuses?
Produce a mucus that protects the nose from pollutants, micro organisms dust and dirt
What is the location of the carotid sinus and what does it detect?
Base of the internal carotid artery just above bifurcation of common carotid artery.
Sensitive to arterial pressure changes which is important in regulating and maintaining blood pressure
Where do the ducts for the submandibular salivary glands open into the mouth?
Adjacent to the 2nd molar, under the tongue
Describe the location of the 4 sinuses
Frontal - most superior of the sinuses just above the eyebrows and close to the midline of the face
Ethmoid - either side of the nose between the eyes
Maxillary - the largest of the sinuses located in the apples of the cheeks
Sphenoid - Most posterior of the sinuses near the ear
Why is infection spread easily between the sinuses?
Due to the close proximity of the sinuses and also its continuation with the nasal cavity
